Question

What would be new resistance if length of conductor is doubled and thickness is
halved ?

Answer 1

As we know resistance R=ρL/A -------------1
now length=2L
A=A/2
SO new reistance R1=ρ2L/A/2
R1=4ρL/A
R1=4(ρL/A)
SO new reistances almost increase by 4 times

Answer 2

Hey mate !!!
upper picutre shows the ratio of conductor of two resistance.


now.

here is your answer :-


R = 2* l * roh / area /2 .


now ,

R' = 4 * original resistance .


hence , the new resistance comes out to be = 4 times of original resistance .



hope it helps !!